Series and Parallel Resistor Calculator
Fill in the value and the answer updates as you type.
How the Series and Parallel Resistor Calculator works
In series the values add: R = R₁ + R₂ + … In parallel the reciprocals add: 1/R = 1/R₁ + 1/R₂ + … Parallel resistance is always smaller than the smallest resistor. Enter values separated by commas or spaces. Example: with the default values, series resistance comes to 650 Ω.
Inputs and results
The Series and Parallel Resistor Calculator takes 1 input and gives 3 results.
What you enter
- Resistor values (comma separated) (Ω) — starts at 100, 220, 330.
What you get
- Series resistance (Ω)
- Parallel resistance (Ω)
- Number of resistors
Example: Series and Parallel Resistor Calculator with the starting values
With resistor values (comma separated) 100, 220, 330 Ω, the calculator returns:
| Series resistance (Ω) | 650 |
|---|---|
| Parallel resistance (Ω) | 56.9 |
| Number of resistors | 3 |
Change any value above and the results update straight away.
Series and Parallel Resistor Calculator FAQ
How do I use the Series and Parallel Resistor Calculator?
Enter resistor values (comma separated) in the fields, then read series resistance (ω), parallel resistance (ω) and number of resistors in the result panel. The answer updates as you type, and you can press Calculate or Enter to refresh it. Use “Copy link” to share your exact numbers with someone else.
What does the Series and Parallel Resistor Calculator calculate?
Total resistance of resistors in series and in parallel. It returns series resistance (ω), parallel resistance (ω) and number of resistors from the 1 value you provide.
What values does the Series and Parallel Resistor Calculator start with?
It opens with resistor values (comma separated) 100, 220, 330 Ω so you can see a working result straight away. Replace them with your own numbers, or press Reset to return to these starting values.
Is the Series and Parallel Resistor Calculator free and private?
Yes. It is free, needs no account, and runs in your browser, so nothing you type is sent to or stored on our servers. See the Privacy Policy for details.
Can I rely on the Series and Parallel Resistor Calculator for important decisions?
Treat the result as a well-rounded estimate. Real situations often have details a general calculator cannot know, so confirm important decisions with a qualified professional. See the Disclaimer for more.